De novo myeloid sarcoma as a rare cause of small bowel obstruction: CT findings and histopathologic correlation.

Small bowel obstruction caused by myeloid sarcoma in a patient with any hematological abnormality is very rare. Myeloid sarcoma occurs most commonly in patients with acute myelogenous leukemia (AML) and less with other hematological disorders. A 57-year-old female presented with abdominal pain, nausea, vomiting, and constipation. Radiological studies showed concentric bowel thickening in distal ileum that caused nearly total luminal compromise and signs of obstruction in proximal ileal bowel loops. She underwent laparotomic surgery and ileal resection was done. Diagnosis of myeloid sarcoma was made by histopathological examination of surgical specimens. Bone marrow biopsy was done to rule out systemic acute myelogenous leukemia (AML). Results of bone marrow biopsy were within normal limits. Finally, the patient was diagnosed as de novo myeloid sarcoma. Although the histopathological examination makes a definitive diagnosis, imaging allows to locate the lesion, evaluate its complications, and guide for correct biopsy. Accurate diagnosis of myeloid sarcoma has important prognostic value as transformation to AML can happen without chemotherapy or stem cell transplantation.